کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5542924 1553926 2017 26 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Genetic parameter estimates for temperament, heifer rebreeding, and stayability in Nellore cattle
ترجمه فارسی عنوان
ارزیابی پارامترهای ژنتیکی برای خلق و خوی، تلقیح مجدد گوساله و ماندگاری در گاو نولور
کلمات کلیدی
طول عمر، آزمایش سرعت پرواز، همبستگی ژنتیکی، واکنش پذیری، صفات تولید مثل،
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
چکیده انگلیسی
The aim of this study was to estimate heritability for five temperament and two reproductive traits in Nellore cattle and to estimate genetic and phenotypic correlations among them. Temperament was evaluated using the movement (MOV), tension (TEN) and crush (CS) scores (measured with animals inside the squeeze chute) as well as the flight speed (FS) and temperament score (TS). Reproductive traits included i) heifer rebreeding (HR), which evaluates heifers' ability to become pregnant, given that they had calved once; and ii) stayability (STAY), which measures cows' ability to calve at least 3 offspring before reaching 65 months of age. We used Bayesian inference and Gibbs sampling in a two-trait analysis to estimate genetic parameters applying a linear model for FS and threshold models for MOV, TEN, CS, TS, HR and STAY. The animal model included contemporary group as a fixed effect, direct additive genetic and residual effects as random effects, and animal age at yearling as a covariate (with linear and quadratic effects). Heritability estimates for MOV, TEN, CS, FS, TS, HR and STAY were 0.14 ± 0.04, 0.11 ± 0.03, 0.09 ± 0.03, 0.22 ± 0.02, 0.19 ± 0.04, 0.13 ± 0.02 and 0.13 ± 0.02, respectively. The genetic correlation estimates were low to moderate and the highest values (in magnitude) were − 0.19 ± 0.21 (HR-CS), − 0.21 ± 0.15 (STAY-TEN) and − 0.24 ± 0.16 (STAY-CS), indicating that the selection to improve cattle temperament does not negatively affect HR and STAY. These results indicate that all traits had sufficient genetic variability to respond to direct selection; however, given the low estimated heritability, we expect to see only long-term genetic changes. Genetic correlations showed that there is no antagonism of temperament with fertility and longevity; however, we recommend including these traits as selection criteria in Nellore breeding programs to obtain satisfactory genetic changes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Livestock Science - Volume 206, December 2017, Pages 45-50
نویسندگان
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